JP2012208158A - Method for storing pellicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for storing pellicles, even in storing, transporting, and opening, being unlikely to generate dust and preventing contamination of a product stored in a bag, especially, the pellicle stored inside a pellicle case.SOLUTION: The method for storing pellicles includes: putting the case storing the pellicle in a first bag for cleanliness specifications and closing its opening; putting it in a second bag with antistatic function and closing its opening; and further putting it in a third bag with the antistatic function and tightly sealing it.

Description

  The present invention relates to a pellicle storage method for storing a product (particularly a pellicle) manufactured in a clean room.

  A pellicle for lithography manufactured in a clean room is stored in a dedicated container and then stored in a resin bag. In order to prevent charging of the pellicle container (case) and the pellicle, an antistatic type bag has generally been used.

  In the case of an antistatic type bag, an antistatic agent is kneaded or a metal thin film is deposited on the surface to give conductivity to the bag. Depending on the transport state and environment of the container, the pellicle container contained in the bag may be contaminated, or when the pellicle container is removed from the bag and the lid is opened, the anti-static agent attached to the pellicle container lid etc. In some cases, the pellicle stored in the container was contaminated.

  In view of the above circumstances, the present invention is a pellicle that is less likely to generate dust during storage, transportation, and opening, and that does not contaminate the product stored in the bag, particularly the pellicle stored inside the pellicle container. It is an object to provide a storage method.

The present invention is for solving such problems. In the pellicle storage method of the present invention, the container storing the pellicle is placed in a clean first bag, and the mouth is closed. It is characterized in that it is put in a second bag having an antistatic function and the mouth is closed, and further sealed in a third bag having an antistatic function.
Bag of the clean specification, which has been the least cleanliness 1000 produced in the following clean room cleanliness management bag having the antistatic function is at least 9.9 × 10 ¹¹ Ω / cm ² or less of the surface Resistant and antistatic properties. The sealing operation is performed in a clean room with a cleanliness level of 1 or higher.

  According to the present invention, a clean bag is used for the innermost first bag, and an antistatic type bag is used for the second and third bags. It is possible to prevent foreign matter from adhering and to minimize the electrification until the container is removed from the bag, thereby preventing the product from being soiled.

It is a schematic explanatory drawing which shows the typical embodiment of the pellicle storage method of this invention.

  The present invention relates to a pellicle storage method for storing a pellicle container in which a pellicle is stored in a clean room, and the pellicle container in which the pellicle is stored is connected to an antistatic clean bag, an antistatic bag, and an antistatic bag from the inside. It is housed and packaged in triplicate in order to prevent contamination of the pellicle container, and thus the pellicle stored inside, by preventing the pellicle container from directly touching the bag containing the antistatic agent, and electrostatic damage due to charging of the bag Basically, this is prevented by the innermost clean bag.

Hereinafter, the present invention will be described in more detail with reference to the drawings.
In FIG. 1, a pellicle container 2 in which a pellicle 1 is housed is housed in a clean first bag 3 and is housed in a second bag 4 having an antistatic function outside thereof, and further an antistatic function is disposed outside thereof. Is stored in a third bag 5.
The size of the bag used in the present invention is not particularly limited as long as it is a size that can store a pellicle storage container (case) and can store a bag stored inside the outer bag. Regarding the thickness, when closing the mouth of each bag, for example, when it is closed by heat sealing, it is preferable that there is a certain thickness so that the bag is not softened and is not torn or cut. On the contrary, if the thickness is so large that it is difficult to fuse, the sealing may not be performed properly, so that the thickness is preferably 50 to 200 μm.

  The material of the bag is not particularly limited, but for the bag (first bag) that comes into contact with the innermost pellicle container, the bag is made of only resin such as polyethylene, nylon, polypropylene, polyester, or these are appropriately laminated. It is preferable to use one. Since the first bag is directly in contact with the container containing the product, it must have a clean specification and a cleanliness controlled product manufactured in a cleanroom with a cleanness of 1000 or less.

The first bag is stored in the second bag. About this 2nd bag, like the 1st bag, it consists of resin, such as polyethylene, nylon, a polypropylene, polyester, and what added the metal thin film to these resins, added the antistatic agent, and also said resin And the like in which the antistatic function is added to the laminate. As long as it has antistatic performance that is generally used as antistatic performance, it has a surface resistance of at least 9.9 × 10 ¹¹ Ω / cm ² , which is a general performance as an antistatic bag. It is desirable.

The pellicle container placed in the second bag is further stored in the third bag. Since the third bag is in direct contact with the outside, the third bag is opened immediately before being carried into the clean room so as not to bring outside dirt into the clean room.
Therefore, according to the cleanliness of the clean room to be carried in, the third bag may be further accommodated in the fourth bag, the fifth bag, and the like.

As for the material of the third bag, like the second bag, it is made of a resin such as polyethylene, nylon, polypropylene, polyester, etc., those obtained by depositing a metal thin film on these resins, those added with an antistatic agent, and further, Examples include those obtained by laminating a resin and imparting an antistatic function.
The same applies to the fourth and subsequent bags.

Examples will be described below. The clean specification bags used in the following examples, reference examples and comparative examples are polyethylene bags manufactured and washed in a clean room with a cleanliness of 1000 or less. A polyethylene bag with an antistatic function (antistatic property with a surface resistance of at least 9.9 × 10 ¹¹ Ω / cm ² or less) added with an agent was used.

[Example 1]
First, a pellicle container containing a pellicle was placed in the first bag of clean specification having a thickness of 70 μm to the innermost part of the bag, and the bag mouth was closed by heat sealing. Next, a first bag containing a pellicle container was placed in a second bag, which is an antistatic bag having a thickness of 70 μm, and the mouth of the bag was closed with a heat seal.
Finally, this was put in a third bag which is an antistatic bag having a thickness of 100 μm, and the mouth of the bag was closed with a heat seal. This was housed in a cardboard box containing a cushioning material, sealed and placed on a vibration tester, and subjected to vibration for 24 hours at an acceleration of 1 G in the vertical direction of 10 Hz.

Next, when this product was brought into a clean room and opened, what appeared to be an antistatic agent in white on the surfaces of the second and third bags was bleeding out. This was also attached to the surface of the first bag, but the container surface in it was clean, and inspected with a 300,000 lux condensing lamp in a dark room in a clean room, but no adhered foreign matter was found. It was.
Further, the storage container was opened and the product (pellicle) was inspected by the above method, but there was no deposit on the product surface.

[Reference Examples 1 and 2]
In Reference Example 1, a clean bag having a thickness of 70 μm was used for the first bag and the second bag, and an antistatic bag having a thickness of 100 μm was used for the third bag. In Reference Example 2, a clean bag having a thickness of 70 μm was used for each of the first bag, the second bag, and the third bag. Except for this, the bag mouth was heat-sealed in the same manner as in Example 1 and a vibration test was conducted for 24 hours. Then, the bag was opened in a clean room, the storage container was opened, the product (pellicle) was taken out, and the inside of the clean room was removed. When inspected with a 300,000 lux condenser lamp in a dark room, any increase in foreign matter was observed on the product. The results are shown in Table 1 together with the results of Example 1.

[Reference Examples 3 to 5]
The test was performed with the same configuration as in Example 1 except that an antistatic bag having a thickness of 70 μm was used as the first bag, and an antistatic bag or a clean bag was appropriately combined with the second and third bags. (See Table 1). When this product was brought into a clean room and opened, the surface of each of the first bag, the second bag, and the third bag was white and bleeded out as an antistatic agent.
Furthermore, it was confirmed that the white powdery thing had adhered also to the container surface. Inspected with a 300,000 lux condenser lamp in a dark room in a clean room, there was a white powdery deposit on the surface of the container. In addition, the container was opened and the product was inspected by the above method, but there was an attached foreign matter, and it was confirmed by microscopic IR spectroscopic analysis that the attached matter was the same component as the antistatic agent contained in the first bag. It was. The results are summarized in Table 1.

[Comparative Example 1]
This is an example of using only an antistatic bag, which has been conventionally performed. A pellicle container containing a pellicle is placed in an antistatic bag having a thickness of 100 μm, the bag mouth is closed by heat sealing, and then the same as in Example 1. After a 24-hour vibration test, the product was opened in a clean room, the storage container was opened, the product (pelicle) was taken out, and inspected with a 300,000 lux condenser lamp in a dark room in the clean room. An increase was observed. The results are shown in Table 1 together with the results of the above examples and reference examples.

1: Pellicle,
2: Pellicle container
3: First bag (clean specification),
4: Second bag (consisting of antistatic bag),
5: Third bag (consisting of an antistatic bag).

Claims (4)

Put the container containing the pellicle in a clean first bag and close its mouth, then put it in a second bag with antistatic function and close its mouth, A method for storing a pellicle, which is sealed in a bag. The pellicle storage method according to claim 1, wherein the clean specification bag is a cleanness-manufactured product manufactured in a clean room having a cleanness of 1000 or less. The pellicle storage method according to claim 1, wherein the bag having an antistatic function has an antistatic property with a surface resistance of at least 9.9 × 10 ¹¹ Ω / cm ² or less. The pellicle storage method according to claim 1, wherein the sealing operation is performed in a clean room having a cleanliness level of 1 or more.

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